Expression of CD44 in pituitary adenoma and its clinical significance

Objective To study the expression of CD44 in pituitary adenoma and investigate its diagnostic and prognostic significance of CD44 in pituitary adenoma.Methods Expression of CD44s and CD44v 5 were detected in human surgically resected samples of pituitary adenoma(20 invasive、18 non-invasive and 6 recurrent pituitary adenoma), using S-P immunohistchemical staining method. Result The positive staining rates of CD44s and CD44v 5 were 75%、35% respectively in 20 invasive pituitary adenomas.The positive staining rates of CD44s and CD44v 5 were 27.8%、22.2% respectively in 18 non-invasive pituitary adenomas.The positive staining rates of CD44s and CD44v 5 100%、66.7% in 6 recurrent pituitary adenoma respectively. The positive staining rate of CD44s are significantly higher in invasive and recurrent pituitary adenoma than in non-invasive pituitary adenoma(P0.01).Low levels of CD44v 5 expression were observed in both invasive and non-invasive pituitary tumor and there was no significant difference. Conclusion The results suggest that higher expressions of CD44s in invasive pituitary adenoma were correlated with pituitary adenoma invasiveness,CD44s may play an important role in invasive pituitary adenoma and can be used for diagnosis of invasive pituitary. Lower expression of CD44v 5 in pituitary adenoma was not related with invasiveness of pituitary adenoma.While the higher expression of CD44s and CD44v 5 show the poor prognosis of recurrent pituitary adenoma.